I've been experimenting with the 1 gallon mylar ziplock bags. The idea is fill, add the O2 absorbers, squeeze out air and ziplock it close. There is about an inch or so of mylar above the ziplock so I am then heat sealing it with the intent that the heat seal will be the relied on seal and the ziplock is both a backup and a way to start using a bag's contents and yet still be able to sort of seal it between uses.
A plus is that if you're not able to buy in large quantities, you can add to a bag over a couple of trips until it's filled zipping it closed in between, then when fill heat seal and start on another one. I had looked at large amounts of some items but with shipping it turned out to be cheaper for me to just buy smaller amounts from local stores.